Raising and lowering apparatus



Z4, 1930.- E. H. REMDE v RIASING AND LOWERING APPARATUS 4 Sheets-Sheet Fil-ed Dec. 19 192] l/vvE/vrae:

June 24, 1930.

E. H. REMDE RAISING ND LOWERING APPARATUS Filed Dec. 19. 1921 4 sheets-sheet 2 Arm/wry 24, 1930. E; H', REMDE 1,767,095

RAIsING AND LowERING APPARATUS Filed Dec, 19. 1921 sheets-sheet 5 'WA www ww 19 54 52 f7@ 67254 :im l

Patented June 24, 1930 UNITED STATES PATENT orifice EDWARD H. REMDE, OF CLEVELAND, OHIO, ASSIGNOR TO THE BAKER-RAULANG COMPANY, OF CLEVELAND, OHIO, A CORPOBJATON OF OHIO RAISING- AND LOWER-ING APIPAR-AIUE:v

Applcatioiiiled December 19, 1921. Serial No. 523,286.

My invention relates to apparatus having an elevating member and means for st opping the movement thereof in one direction or in either direction. More particularly,

the invention relates to an elevating industrial truck, in which an improved stopping means cuts outrthe elevating power mechanism as the elevating member reaches or approaches its limit of movement.

One object of the invention is to provide an improved cut-out niechanismof simple construction.

Another object of the invention is to provide an improved cut-out mechanism in which the elements are co-related to permit of overrun due to inertia without damage to the contact or .other elements of the mechanism.

Another object of the invention is to pro- `vide in the circuits which supply current to drive a motor in opposite directions, an improved cut-out mechanism operable by the member, which is driven in either direction by the motor, when it reaches predetermined positions.

Other objects of the invention will be apparent to those skilled in the art to which my invention relates from the following description taken in connection with the acn companying drawings.

In the drawings, Fig. 1 is a side elevation (partly broken away) of an elevating platform truck having a cut-out mechanism enbodying my invention.

Fig. 1a is a fragmentary plan view on the line 1-1EL of Fig. 1, with parts broken away.

Fig. 2 is a section on the line 2-'2 of Figs. 1 and 4, the elements shown beingpin neutral position.

Fig. 3 is a fragmentary elevation looking at the `elements shown in Fig. 2 on the line 3-3 thereof.

Fig. 4 is a section on the line 4 4 vof Fig. 2.

Fig. 5 is a section on the line 5 5 of Fig. 4:.

Fig. 6 is a section similar to Fig. 4i, but showing the elements in one operated posi- 131011.' n

lF ig. 7 is a View similar to Fig. 3, but showing the elements. in operated positions-one position in full lines and the other position-in dotted lines.

Referring to the drawings, 1 indicates as 5.;

an. entirety a; truck. 2 indicates, the truck frame comprisinga section 3, which preferably carries'the electric battery or batteries 4, and a section 5, which is relatively low and is adapted to support an elevating platform 6 and, by preference, a mechanism 7 for raising and lowering the said platform and an electric motor 8 for operating said mechanism. 8a indicates a lever which operates a controller (not shown) for controlling the electric circnit to the motor 8, to drive it in'opposite directions. 9, 10, indicate the pairs of wheels on which the frame 2 is mounted. The wheels 9, 10, or either pair thereof, may be steerable, the operating connections 11, therefore, being actuated by a suitable hand operated device-for example,

a lever 12. 13 indicates an electric motor for driving the wheels 9. 14 indicates a lever which operates a controller (suitably mounted in a casing 15) for controlling theelectric circuit tothe motor 13. 16 is a brake pedal for operating a brake mechanism 16-see ,l dotted linesin Fig. 1. It will be understood a cross bar 7 to which is connected, preferably at a point midway between the sides of the frame, the outer end of a plunger or thrust member 7d. he inner end of the plunger fit-s within a tubular portion 8l of a casing 8, which houses a suitable reduction gearing for the motor 3. The inner end of the plunger is provided with screw threads and engages a threaded member driven through said gearing by the motor 8, whereby the frame 7a is moved endwise in one direction or the other accordingly as the controller handle 3a is operated. 6n indicates pairs of inclines on the under side of the platform 6 and fixed thereto in any desired manner. 7c indicates pairs of shoes, preferably rollers, carried by the frame 7a and disposed so that each thereof will engage one of the inclines 6, their arrangement preferably being such that the engagement of all the shoes 7 e with their respective inclines will occur substantially simul taneously, so that during the raising and lowering of the platform 6, the latter will maintain a substantially horizontal position. lVhen the platform 6 is in its lowermost position the frame 7a is at the limit of its movement in the rearward direction. If the motor 8 is operated to move the frame 7a forwardly (toward the left in Fig. 1), the rollers 7 e will engage the inclines 6il and through them raise the platform 6 as shown in Fig. 1. To prevent endwise movement of the platform incident to the action of the rollers 7 e against the inclines, I provide a pair of links 6", each pivoted at its opposite ends to the platform 6 and frame 5.

17 indicates a link pivoted at 13, to the platform 6 or the raising and lowering mechanism 7 therefor, at one end, and its opposite end, pivoted at 19 to an arm 20, which forms one element of the limiting means or cut-out mechanism, indicated as entirety at 21, which is adapted to break the electric circuit to the motor 8 the patform 6 approaches the. end of movement upwardly or downwardly accordingly as the motor 8 is operated to move it. The arm 2O is pivoted on a stud shaft 22 mounted in an angle plate 23, seated on and secured in any well known way to the ll..frame 5a, which forms a part of the frame section 5. 24 indicates a base plate secured in any suitable manner to the plate 23, as by bolts 25. 26 indicates a cover or casing engaging the plate 24 near its side edges and secured thereto, preferably by the bolts 25 and separate bolts 27.

The casing 26 is arranged to enclose certain of the elements of the cut-out mechanism to be presently referred to. 28 1nldicates a rock shaft extending tl rough a tubular boss 29, preferably formed integral with the plate 24. The shaft 2S is preferably mounted in a sleeve bearing 30, supported in the boss 29. At its inner end, the rock shaft 28 carries an arm 31, which will be later described. At its outer end, the rock shaft carries a yoke or U-shaped member 32, the legs 32, 32", of which are diS- posed upon opposite sides of and in the path of movement of a device 33 projecting later ally from the arm 20. The device 33 preferably comprises a pin or bolt 34 carrying a roller 35 which makes engagement with the legs 32a, 32b and through such engage ment serves to swing the yoke (see Fig. 7) and through it to rock the shaft 28 in one direction or the other. The bolt 34 is secured in an opening formed in the arm '20 by a nut 34a. 32 kindicates inserts preferably formed of steel or other suitable material and secured to the legs 32a, 32", in position to be engaged by the roller 35. In the operation of the arm 2() about its pivot, the roller 35 will engage one of the legs of the yoke 32 and swing it laterally until the adjacent leg is positioned beyond the circular path described by the roller 35, the legs being so disposed and spaced that when either is moved this dist-ance the cut-out vmechanism will operate and break the circuit to the motor, in the manner hereinafter set forth. If however, due to inertia of the armature shaft, the platform and other elements connected to it, the arm 2O is carried aboutits pivot a greater distance than that necessary to operate the cut-out mechanism, the roller 35 will simply ride on the adjacent insert and impart but slight further movementto the rock shaft 28.

36 indicates a spring coiled around the rock shaft 2S or by preference the inner hub portion of the arm 3l, as shown in Fig. 2. The opposite ends 36, 36b of the spring 36 are crossed and disposed on the opposite sides of a pair of lugs 37, 38, disposed one above the other when the arm 31 is in normal position, the former being provided on the inner side of the arm 31 and the latter being provided on the inner face of the base plate 24. As a result of this construction, it will be understood that movement of the arm 31 in either direction will separate the arms 36, 36", (see Fig. 6) and hence put the spring 36 under tension, and thereby normally exert 'an'influence to return the arm 31 to neutral or mid-position. 39, 39a, indicate a pair of contacts of suitable construction, mounted Yon the base plate 24 and connected by leads 39 to proper terminals on the controller (already referred to) for the motor 8, whereby the motor may be stopped and reversed accordingly as the controller is operated either to raise or lower or stop movement of the platform 6. Each of the contacts 39, 39, preferably comprises a pair of spaced plates arranged to receive between them a switch blade 40. 41, 41a indicate a pair of stud shafts extending through openings (but insulated from the walls thereof) formed in the base plateV 24 and secured therein by nuts 42 engaging the oppositefaces of the plate. The shafts 41, 41a, are connected, preferably on the outer side of the base plate 24,`by a plate 41h, which is provided with a connector 41 for a feed wire 43. 44, 44a, indicate levers pivotally mountedA on the shafts 41, 41a. Corresponding arms 44., 449', ofthe levers 44, 44a, engage cams 45, 45a, respectively, carried by the free end of the arm 31, while the opposite corresponding arms 49, 49a, of the levers44, 44a, operatively connected with the switch blades 40 serve to swing them into and out of engagement with the contact plates of the contacts 39, 39a, respectively, as will later be set forth. As shown in Figs. 4 and 6', the cams are oppositely disposed so as to swing one of the levers 44, 44*1about the adjacent shaft when the arm 31 ismovedin f one direction and to swing the other lever about its shaft when the arm 31 is moved in the opposite direction. The levers 44, 44a,V

are provided with lugs `46 and these lugs are spring 47 which tends to swing them about their axes in the direction to maintain vthe lever arms 44, 44a, in engagement withthe cams 45, a. The switch blades40 are preferably pivotally mounted 'on the stud shafts 41, 41a, and are moved thereabout by the adjacent arms 49, 49a, of the `levers 44, 44a, each being preferably operatively connected, by devices indicated as an entirety at 48, to the adjacent lever arm'in a manner which permits a snap action in breaking the circuits through the contacts 39, 39a. Of the devices 48, 50, 51, indicate a pair of lugs .projecting laterally from the member 49 or 49a across the path of movement of the adjacent switch blade 40 and spaced from each other adistance greater than the width of said blade. 52 indicates a spring, one end 53 thereof being bent or hooked around theouter sideof i the blade 40 and its other end extending around the hub of the.` adjacent lever and disposed behind a lug, 54 preferably provided on the lever 44 and 44a. tion, the cam 45 will move the arm 44', which in turn will move the lever 44 and arm 49, the movement of the former acting to put the spring 52 under tension. As the arm 44 approaches the limit of its upward movement, as it rides the adjacent cam 45, the lug engages the edge of the blade 40 and moves the latter with it. As soon as the blade 40 swings far enough to permitthe spring 52 to overcome the friction between the blade and the contact plates, the spring will operate the blade with a quick movement to the position shown in Fig. 6, against the lug 51.

Fig. 4 shows the elements of the *cut-out mechanism in mid-position and arranged to transmit current to the termina-ls on 'the InV operay in Fig. 7, thereby swinging the .arm 31' laterally and breaking the circuit throughthe switchbla'de 40 and contacts 39, as shown in F ig.` 6, thus stopping the motor. If the platform 6 moves downwardly, the link 17 will movethe .arm 20 in the opposite direction and as the platform 6 approaches the limit of its downward movement, -the `arm 2O through the roller 35 willswing the yoke 32 to the position shown in dotted lines in Fig.-

7, thereby swinging the arm 31 and breaking the vcircuit through the switch blade 40 and `contacts 39a, thus stopping the motor.

vIt will be noted that the arm 31 carries two cams 45,454, so disposed and arranged that only one lever is operated when the arm 31 swings laterally in either direction. Accordingly, the breaking of one circuit to stop the operation of motor 8 inone direction, does not affect the other circuit for operating .the motor in the opposite direction. Y f

:It will also be noted that after onecircuit has been Vbroken Vto stop the motor 8 and following the operation of theV motor in the opposite direction and movement'of the platform 6 accordingly, the arm 2O will move toward its Vmid-position. As the arm 2O so moves, the'spring 36 will act on the arm 31 and swing it and theyoke v32 to normal position. Thearm 31 will in turn permit the adjacent lever 44 or 44a to swing backwardly and vsuch lever acting through the lug 51, will move the adjacent switch blade 40 into engagement with the adjacent contacts. Due to the shape of the cams 45, 45 this reengagement will be effected relatively quick.

The link 17 or its connection 'with the platform 6 and arm 20, at'either or both ends may be made adjustable in order to vary the engagement of the roller 35 with the legs 32a, 321. As shown in Fig. 7 the link V17 is provided at one end with screw threads 17a, such screw threaded end 'itting a screw threaded opening ina connecting device 17", and permitting adjustment forthe purpose just referredto.

From the foregoing description it will be seen' that I have provided a relatively sim truck, such as shown herein for illustrative purposes, enables the operative to control the platform with great facility, as he is only called upon to start the motor 8 in either direction, the cutout mechanism serving to stop the motor at the desired point.

As the cut-out mechanism is or may be arranged to break the circuit and stop the movement of the platform at substantially the end of its movement in either direction, such operation may be entirely relied upon by the operative in manipulating the truck. Accordingly aside from acting as a safety device, it may serve as a positive operating means for use in connection with the raising and lowering of the platform.

To those skilled in the art of making apparatus of the class described, many alterations in construction and widely differing embodiments and applications of my invention will suggest themselves without departing from the spirit and scope thereof.

My disclosures and the description herein are purely illustrative and are not intended to be in any sense limiting.,V

`What I claim is:

1. In apparatus of the class described,V

the combination with a frame having a platform movably mounted thereon, of means, including a motor on said frame for raising and lowering said platform, a source of current supply, an electric circuit, including a pair of leads through one of which the circuit is completed to drive said motor in one direction and through the other of which theA circuit is completed to drive the motor in the opposite direction,

` a controller for said circuit, a switch device interposed in each of said leads, a mechanism for throwing said switch devices as said platform reaches its limit of movement in either direction, said mechanism comprising a movable device common to and arranged to operate either of said switch devices and having a pair of arms and a member connected to said platform and operable to engage one arm when the platform approaches its limit of movement in' one direction to operate one of said switch devices and to engage the other arm when the platform approaches its limit of movenient in the other direction to operate the other switch device.

2. In apparatus of the class described, the combination with a frame having a platform inovablyy mountedV thereon, of means, including a motor on said frame for raising and lowering said platform, a source of current supply, an electric circuit, including a pair of leads through one of which the circuit is completed to drive said motor in one. direction and'through the other of which the circuit is completed to drive the motor in the opposite direction, a

controller for said circuit, a switch device interposed in'each of said leads, a mechanism for throwing said switch devices as said platform reaches its limit of movement in either direction, vsaid mechanism comprising a movable device common to and arranged to operate either of said switch devices and having a pair of arms and a member connected to said platform and operable to engage one arm when the platform approaches its limit of movement in one direction to operate one of said switch devices and to engage the other arm when the platform approaches its limit of movement in the other direction to operate the other switch device, each of said switch devices being operable without affecting the other switch device.

3. In apparatus of the class described, the combination with a frame having a platform movably mounted thereon, of means, including a motor on said frame for raising and lowering said platform, a source of current supply, an electric circuit, including a pair of leads through one of which the circuit is completed to drive said motor in one directionand'through the other of which the circuit is completed to drive the motor in the opposite direction, 'a controller for said circuit, a switch device interposed in each of said leads, a mechanism for throwing one of 'said switch devices as said platform reaches `its limit of movement in either direction,

said mechanism comprising a movable device common to andv arranged to operate either of said switch devices and having a pair of arms and a member connected to said platform and operable to engage one arm when the platfom approaches its limit of movement in one direction to operate one of said switch devices and to engage the other varm when the platform approaches its limit of movement in the other direction to operate the other switch device, said member being movable relative to either arm after' operating it to permit of overrun of said platform and motor.

4c. In apparatus of the class described, the combination with a frame having a platform movably mounted thereon, of means, ineluding a motor on said frame for raising and lowering said platform, a source of current supply, an electric circuit, including a pair Of leads through one of which the circuit is completed to drive said motor in one direction and through the other of which the cirkcuitis completed to drive the motor in the Y opposite direction, a controller for said circuit, a switch device interposed in each of said leads, a mechanism for throwing one of said switch devices 'as said platform reaches its limit of movement in either direction, said mechanism comprising a movable device common to and arranged to operate either of said switch devices and having a pair of arms and a member pivoted on said frame in operative relation to said arms and connected to said platform, whereby movement of the latter in one direction will swing said member into engagement with one arm to effect operation of one switch device and movement of the platform in the other direction will swing said member into engagement with the other arm to effect operation of the other switch device.

5. In apparatus of the character described, the combination with a pair of relatively movable members, of means for operating one of said members relative to the other in r opposite directions, said means including separate leads each having a switch therein, a pair of swingable devices on one of said members movable to either side of a plane cutting the axes on which -said devices swing, one device being connected to the other member and carrying a tappet and the other device comprising arms extending laterally to either side orp said plane and disposed in the path of movement of and arranged to be engaged by said tappet whereby the latter siifings said device to one side or the other of said plane, and means actuated by said last referred to device for opening one of -said switches accordingly as said device is swung in one direction or the other direction.

G. In apparatus of the character described, the combination with a pair of relatively movable members, of means for operating one of said members relative to the other in opposite directions, said means including separate leads each having a switch therein, a pair of swingable devices on one of said members movable to either side of a plane cutting the axes on which said devices swing, one device being connected to the other member and carrying a tappet and the other device comprising arms extending laterally to either side of said plane and disposed in the path of movement of and arranged to be engaged by said tappet whereby the latter swings said device to one side or the other of said plano, and means actuated by said last referred to device for opening one of said switches accordingly as said device is swung in one direction or the other direction, each oi" said arms being shaped to permit movemeut et the rst mentioned device after it has operated the other device and the switch operating means due to inertia of said movable member and its operating means.

7. In apparatus of the character described, the combination with a pair of relatively movable members, of means for operating one of said members relative to the other in opposite directions, said means including separate leads each having a switch therein, a roclr shaft carried by one of said members, said shaft carrying an element common to and arranged to operate one or the other of said switches and a pairof spaced parts, an

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